Effects Of Reducing Chemical Fertilizer Application And Combining Organic Fertilizer And Trichoderma On The Quality And Fertilizer Utilization Of Thin-skinned Melo

Orient melon is an important economic crop in facility horticulture cultivation in Heilongjiang Province,which has high edible value and economic value.At present,the excessive use and inaccurate usage of chemical fertilizers in the production process of orient melon resulted in the deterioration of fruit quality.Therefore,in this study,the effects of chemical fertilizer reduction combined with organic fertilizer and Trichoderma agent on melon growth,fruit yield and quality and fertilizer utilization were investigated under the condition of chemical fertilizer reduction,and the dosage and way of conventional fertilization of melon production in local facilities were used as the control.All and half of the chemical fertilizer were replaced by organic fertilizer,and the same amount of nitrogen,phosphorus and potassium fertilizer was applied with Trichoderma agent at the same time,The results were as follows:1.Chemical fertilizer reduction combined with organic fertilizer and Trichoderma agent could promote the plant height and leaf area of "CH7",but there were no significant differences in stem diameter of "CH7".Reduction of chemical fertilizer combined with organic fertilizer and Trichoderma agent significantly promoted the yield of orient melon,and the fruit weight per plant of orient melon was the highest with half of chemical fertilizer +organic fertilizer + Trichoderma(T3 treatment).2.Compared with CK(no fertilizer treatment)and CK1(conventional fertilization used by the farmers),the treatments of chemical fertilizer reduction combined with organic fertilizer and Trichoderma agent(T1,T2 and T3 treatments)could significantly increase the contents of soluble sugar and fructose,glucose and sucrose in mature melon fruits through promoting the activities of sucrose synthetase-synthesis direction and sucrose phosphate synthase and inhibiting the activities of sucrose synthetase-decomposition direction and acid invertase,especially T3 treatment.In addition,the treatments of chemical fertilizer reduction combined with organic fertilizer and Trichoderma agent still increased the contents of soluble protein,soluble sugar,Vc and nitrate nitrogen in ripe fruits.3.The combined application of reduced chemical fertilizer,organic fertilizer and Trichoderma agent could promote the absorption of nitrogen(N),phosphorus(P)and potassium(K)in stem,leaf,petiole and fruit,and the accumulations of N,P and K in fruit and leaf were much higher than that in stem and petiole.Compared with CK1,the treatments of reduced chemical fertilizer combined with organic fertilizer and Trichoderma agent(T1,T2 and T3)increased nitrate reductase activity and glutamine synthase activity in leaves.The treatments of chemical fertilizer reduction combined with organic fertilizer and Trichoderma agent(T1,T2 and T3 treatments)could significantly promoted the activities of sucrase,soil cellulase,soil peroxidase and soil hydrogen peroxide in 20 cm and 40 cm rhizosphere of orient melon,and the activities of soil urease,soil phosphatase and soil polyphenol oxidase in the rhizosphere layer 20 cm of T1,T2 and T3 were significantly promoted,regulating the contents of rhizosphere soil nitrate nitrogen,ammonium nitrogen,effective phosphorus and available potassium in 20 cm and 40 cm,which promoted the absorption and utilization of N,P and K nitrogen uptake and utilization in orient melon plants.4.The treatments of chemical fertilizer reduction combined with organic fertilizer and Trichoderma agent(T1,T2 and T3 treatments)could obviously improved the activities of soil sucrase and soil phosphatase.The activities of urease and polyphenol oxidase in 20 cm rhizosphere layer of orient melon under T1,T2 and T3 treatments were markedly higher than those under CK and CK1 treatments.Compared with CK,fertilization treatment could effectively increase the contents of nitrate nitrogen,ammonium nitrogen,effective phosphorus and available potassium in the rhizosphere soil of melon plant,while The treatments of chemical fertilizer reduction combined with organic fertilizer and Trichoderma agent might adjust the soil enzymes activities and the contents of available N,P and K,which notably improve the utilization rates of N,P and K for orient melon,and The N,P and K utilization rates of orient melon plants in T3 treatment were increased by 19.95%,8.17% and44.71%,respectively.The N,P and K agronomic efficiency of orient melon plants in T3 treatment were increased by 296.29kg/kg,295.29kg/kg,310.00kg/kg,respectively.